Dr. Phil Metzger, who worked for a long time at Swamp Works before taking a research position at a university. Still very much involved in processing regolith and moon bases. https://twitter.com/DrPhiltill
NASA also hosts an annual competition around regolith collection called the NASA Lunabotics Competition. The last 2 years have been a little rough, with a cancellation due to government furloughs, then a cancellation due to the pandemic. Swamp Works engineers, technicians, and machinists attend and are often judges. Where they might make 1 or 2 prototypes per year, they're able to see 30-50 different designs and see their performance. The rules are setup to penalize activity similar to the incentives NASA has. Low bandwidth usage, high material collection, and low vehicle weight are all rewarded. https://www.nasa.gov/offices/education/centers/kennedy/techn...
Alabama has had a very good run, accomplishing fully autonomous 10 minute competition runs, avoiding rocks, having a really great systems engineering approach.
There has also been a competition in Hawaii on Mauna Kea periodically. I was at Iowa State in 2014 when we attended. There's an area just west of the visitor center with an environment very similar to the moon. Teams tele-operated the robots from ~30 miles away in Hilo, introducing a time lag in communications. It was a really incredible experience, and a lot of logistical planning to ship a robot, spare parts, and tool to Hawaii. Dremels are never the right tool for the job...but a lot of jobs can be done with a Dremel. Here's a video from Alabama at the same site in 2012. https://www.youtube.com/watch?v=mqWpglIwOr4
Thanks for your most informative post. Elecrochemical oxygen extraction from lunar regolith has been a thing for decades, experiments have even flown on the Vomit Comit to demonstrate effectiveness in lunar gravity.
It's an old well-known proposal to electrolyze molten oxides, isn't it? There is even hope for wide industrial applications on Earth of such technology for coal-free metal production. Though I don't see a particular novelty here and it will be quite hard to pull-off on a moon base (after all, you have to work with high-temperatures and the process is quite power hungry), I am happy to see that work continues in this field.
In space you have a reverse problem: it's difficult to dissipate heat. It's a bit easier to do on moon surface than on an orbital station, but regolith has a limited thermal conductivity, which could be insufficient for an industrial process releasing a lot of waste heat. For obvious reasons we can't simply build wet cooling towers as we usually do on Earth.
I don‘t quite understand why we think humans can survive staying on moon bases or trips to Mars before the problem of cosmic radiation is solved. Going on a trip to Mars and back makes you prone to dying from cancer. Mars doesn‘t have a magnetic field that would shield inhabitants from being bombarded by high-energy particles. How are we going to deal with this?
We know how to shield from radiation, there is no mystery there, just put matter in btween the source and the passengers. It's not easy, but the physics are well understood.
Besides, how do the astronauts on the ISS deal with radiation? Is the ISS somehow better protected near earth than in deep space?
Yes, the ISS has some protection from being in low Earth orbit. But the rate of cosmic ray strikes is still high enough to pose a health risk, so the areas on ISS where astronauts spend most of their time have additional shielding. The material most often used for shielding is polyethylene because it performs better in terms of secondary emissions - heavy elements like lead emit showers of secondary particles when struck by cosmic rays and have to be very thick to contain the secondaries, which is far too heavy to put into space.
Once away from low Earth orbit the shielding on a spacecraft becomes very expensive in terms of size and weight, even when it is the lighter weight polyethylene material.
The problem will be solved in time, and in the meantime, we can solve other problems (like in-situ resource utilization, closed-loop habitation, etc.) in parallel.
> How are we going to deal with this?
I don't have an answer for the journey to Mars itself (and I'm also not sure if there's a consensus on how big a danger would such trip pose) - but you'll definitely want to keep the fuel between the passengers and the Sun. It would likely also be wise to pad the whole vehicle with some dense material - but to do that, you'd really want to have some sort of manufacturing capability in cislunar space, to avoid having to lift all that mass upwell.
As for bases on Moon and/or Mars, the best solution is probably to dig in - find a cave or make a tunnel, set up there, and develop underground. Ground is a very good radiation shield.
This seems relatively unexciting; we've known that the moon has abundant oxygen for decades. The hard part is finding stuff (food, hydrogen, hydrocarbons, etc.) to burn with it.
When species are getting extinct on Earth in our lifetime; many would be happy to give up the Moon for mining.
Is it too political? Well, you drew a tangent; I'm dragging it.
Political:
West was indifferent to the plight/life of middle-east people for oil in 20/21st century. Needed little/no reasons to destabilise. When we can give up part of Earth for mining; I guess we'll think little about Moon when the time(profitable Moon mining tech) suits.
You can concentrate the most damaging industry on the far side.
That said, naked eye cannot see any traces of human civilization at all on the face of the Earth from the Moon. Even city lights at night are too weak to be seen without a telescope.
So why should we be able to see traces of lunar industry when looking at the Moon from Earth one day?
Industrial processes are just so power-hungry. We're a long way from mining, smelting etc in space. So many problems to solve, not the least of which is projecting power-generating equipment in the megawatt range into space.
We can start by sending nuclear reactors up there, like the ones NASA is developing for spaceflight[0]. Kilowatts electrical + thermal should be enough to do some basic, very small-scale industrial operations, and expand from there.
Oh with the sun, there is enough energy in space and in the moon (at daytime). You "just" have to focus and redirect it.
And store it for the long nights.
I could see a couple ways out of storing it. Either don't do anything when it's dark, or collect the energy on the other side (or from orbit) and transmit it to the dark side.
Shit, this is what my HN app shows as the article preview:
> British engineers are fine-tuning a process that will be used to extract oxygen from lunar dust, leaving behind metal powders that could be 3D printed into cons
>"Lunar regolith, the thin layer of dusty rock that blankets the Moon, is not so different from the minerals found on Earth. By weight, it contains about 45 percent oxygen which is bound to metals such as iron and titanium, making it unavailable."
>"The electrochemical process takes place in a specially designed chamber - the ones used for research are about the size of a washing machine. Oxygen-containing material is submerged in molten salt, heated to 950 degrees Celsius. A current is then passed through it, which triggers the oxygen to be extracted and migrate across the liquid salt to collect at an electrode, leaving behind a mixture of metal powders."
PDS: Some posters have suggested that the electrification of molten salts to extract oxygen was a process known for a long time. Probably true, but this is the first I've heard of it (Disclaimer: I am not a Chemist or Chemical Engineer... in fact, I'm not even a real Scientist! <g>)
But, this is interesting!
In the case of water, electrolysis yields Oxygen and Hydrogen (is Hydrogen a metal? Some scientists say 'yes -- but only at a very high pressure'). In the case of a metal mixed with Oxygen; an oxide; apparently oxides have to be heated to very high temperatures and mixed with a salt (compare this to H2O being mixed with a salt prior to electrolysis, AFAIK, the salt is just there to make the H2O conductive to a voltage), and then electrolyzed and then you can extract the oxygen.
Now, I wonder if the process could be completed without a salt, because well, H2O can be electrolyzed without a salt -- you just get a whole lot less Hydrogen and Oxygen bubbles -- this is because not as much current is going through the water without the salt added.
That's because water without additives acts as a resistor.
The salt basically makes the solution into less of a resistor, and more of a conductor.
But let's say we wanted to accomplish this feat without adding the salt. How might we accomplish this?
Well, we could raise the voltage to compensate for the resistance that needs to be overcome.
Yes, this would mean lowering the current of the electrodes proportionally.
But, maybe we could use a trick, like the way a Xenon flash bulb is lit -- to make this thing happen.
Basically, in a Xenon flash bulb, a very quickly occurring high-voltage arc pulse first ionizes the Xenon gas, then a secondary much lower voltage (but much higher current) is continuously passed across the now-conductive ionized path blazed by the initial high voltage pulse.
So I wonder if something like that could work to extract oxygen from lunar regolith, without requiring (or requiring as much!) salt... or heck, heat even(!)... perhaps you could do something like get the oxygen out at lower temperatures...
It would just be a question of enough voltage to start the circuit -- and subsequently enough current to sustain it...
It's also equal-and-oppositely possible that all of the above is a complete and total crackpot theory...
...Take all of the above with the proverbial... "grain of salt"... <g>
> PDS: Some posters have suggested that the electrification of molten salts to extract oxygen was a process known for a long time. Probably true, but this is the first I've heard of it (Disclaimer: I am not a Chemist or Chemical Engineer... in fact, I'm not even a real Scientist! <g>)
The mix of molted salts is the liquid where you dissolve the Aluminum oxide. IIRC, you can theoretically try without the molted salt, but the temperature to melt the oxide is much higher, so it is not a practical method without the salt.
One difference is that this process to produce Aluminum you don't make Oxygen. You have big Carbon electrodes, and they get burned.
If you want to produce Oxygen, you probably can replace the Carbon electrode with a Platinum electrode. It would require more energy, and the bubbles will make the process even more complicated. (This should work in a laboratory. To make this safe an efficient at industrial scales, would require a few years of tweaking with the additives, shapes and temperatures. Amway, using Carbon is more efficient, and this variant is too expensive as a method to produce Oxygen for the Earth market.)
This is really stupid. They've managed to take stuff that's so difficult to find that you literally have to go to the freaking moon to get it, and turn it into something that is literally everywhere all over earth. What a bunch of idiots.
On a more serious note, is the high energy demands of this process a blocker at all? Or can we just assume that energy (solar) is abundant on the moon?
I'd say solar panel output would be way more predictable than upon Earth as no chaotic weather systems at play, also larger unfiltered spectrum would mean panels could be tailor made to get higher efficiency than you get per m2 anywhere upon Earth with its atmosphere.
Wouldn't an unfiltered spectrum mean you'd need to tailor your solar panels less, and likely get lower efficiency (fewer watts of electricity per watt of sunlight) than on Earth? You'd still get more watts per square metre, because the atmosphere wouldn't be in the way.
I'm sure the moon has it's own environmental factors that would impact materiel choices and make some more suitable than others. So having a wider spectrum of light at suitable levels to tap into, whilst that opens up the possibility to tap into a larger spectrum at the required power levels to generate electricity. It maybe that being able to use some materials have advantages and tap a part of the spectrum that would not be viable upon earth proves more suitable.
What if, just hear me out, what if the end goal is to use this process one the moon where the input stuff is abundant and the output is going at premium rate?
What stops solar collectors on earth from working consistently is atmospheric interference diffusing the light.
If you can figure out how to avoid creating dust clouds on the moon, which is not a small if, solar concentrators could provide a lot of the heat for the process, reducing the power needs to the electrochemical part.
I haven’t read the original article, but there have been processes for extracting oxygen from lunar regolith for a half century now. I’m not sure what’s new about this one.
In general these processes are energy intensive because they involve temperatures high enough to melt rock. On the Earth that is difficult to achieve because you need to keep the furnace hot. On the Moon with its hard vacuum, a large chunk of rock moved onto insulating material doesn’t radiate much heat. So all you’d need, really, is a large parabolic mirror. The Sun is your power source.
There's a lot of options for getting that energy on the moon mostly various versions of solar either by traditional solar panels or you could use mirrors to concentrate sunlight to provide heat directly.
The latter works pretty well on the moon because the day is pretty long at almost a month. If you get really creative the slow speed means it might be possible to build a giant tracked refinery that slowly circles the moon so it has continuous daylight.
While I appreciate the humor, the crowd here doesn't typically take to it. To answer your question - I do not have much knowledge of available solar energy on the moon versus the Earth, but I think it's safe to assume it would be much less impeded on the moon than on Earth, which has an atmosphere, magnetosphere, and ozone layer at the very least getting in the way of solar rays.
It looks like about 1/3 more energy per area than the surface of Earth at noon. On the moon you should get about a 50% duty cycle of that as opposed to about 20% on Earth (the edges of the day and weather eat a lot of power), so it's safe to say "about three times as much" energy per year.
I wonder if arrays of mirrors (aimed at a heat engine or whatever they use to generate electricity from molten salt) would be cheaper to scale up there.
This process just needs heat so why not skip the electricity step entirely and just have a big refinery follow the sun around the moon. With a 29.5 day... day and a small circumference the you only need to move ~9.5 mph to stay in constant sunlight on the moon.
I wonder if arrays of mirrors (aimed at a heat engine or whatever they use to generate electricity from molten salt)
That seems like a great idea. Find a nice big crater in an area that gets a lot of sunlight and polish the walls of the crater into a parabolic mirror. Put your heat engine at the focus and collect tons of energy. The one drawback: how do you provide cooling? Heat engines are only efficient with a large temperature gradient (Carnot's theorem).
First step to an exo-earth settlement is going to be sending the biggest reactor that will fit on a rocket. Two of them, actually.[1]
Whether its digging, breathing, or making rocket-fuel pretty much everything is going to require, by earth standards, gobs of power. Last thing you'd want to do is operate in a power-starved or even power-adequate environment.
[1]Plus, to be fair, enough backup solar or RTG to keep people alive in case of reactor failure.
Is that feasible? The container for the radioactive fuel must be robust enough to survive a catastrophic failure during launch followed by an an impact on Earth without releasing its contents. Which is possible (RTGs are built that way), but adds a lot of weight.
Not sure, but the article does indicate they're working on reducing energy requirements with a view to making it lunar-feasible.
Engineers will tinker with the process by adjusting the electrical current and reagents to boost the amount of oxygen while trying to reduce the temperature needed to produce it. This will help bring down the energy required, which is already at a premium on the Moon.
It’s the fault of the creator and the community and is on purpose. This site is meant to be for more intellectual discussion and not cheap quips. If you want threads full of one sentence and derailing comments you can visit Reddit: this site is engineered to /not/ become like Reddit.
It's not really fair to pin "fault" on anyone in particular for the culture that develops on any given social media site. These things just kinda emerge.
I think hn itself is a counterpoint to your assertion. The toxic culture hasn't really "emerged" here as it has on countless other platforms, due primarily to ruthless call-out/moderation/shadow banning etc.
Humor isn't toxic. What's toxic is the vituperative snark, contemptuous elitism, low-effort cynicism and outright hatred this community breeds and that dang constantly has to put down because (among other reasons) we have to be pedantic humorless prigs about everything.
I'll take more dumb jokes over yet another diatribe on how Twitter's latest moderation policy changes will lead to mass graves and white genocide any day.
I didn't mean to imply that the particular cultures of the various social media websites are "toxic", they're just all different. Each site has their own style of talking, peculiar grammar rules, appropriate topics, and memes, and all of those things exist on HN too, at least to some extent.
HN post topics are restricted, usually to technical stories or less controversial political topics. Comments tend to be precisely worded, and are often more pedantic. Because of how linking works (or rather doesn't), citations often use a particular format. Comedy is generally discouraged, though is accepted more if (like in Traster's top-level comment in this thread) there's also "legitimate" point attached. If that comment hadn't included the second paragraph, it would probably have been downvoted. All of that is part of the culture of HN, and I wouldn't necessarily call any of it toxic. Some of it follows directly from the site rules and moderation, some follows from the technical limitations of the site, and some just emerges from the sorts of people who happen to use the site.
While occasional humor is welcome, if we reward it too much, then the comments will be full of low-quality jokes. I think most readers here aren’t looking for that.
How this extremely biased and negative comment hasn’t been downvoted, I have no idea. Or perhaps there’s some kind of double sided irony here I’m missing.
Either way, what’s being described is a process to refine materials to be used in space, where currently sending similar materials from the is prohibitively expensive.
The article directly describes the electrolysis process:
>Oxygen-containing material is submerged in molten salt, heated to 950 degrees Celsius. A current is then passed through it, which triggers the oxygen to be extracted and migrate across the liquid salt to collect at an electrode, leaving behind a mixture of metal powders.
And does not contain any mention of a magic catalyst.
You can't breathe that oxygen, however, unless you blend it with 4 parts of nitrogen or something similarly more massive than the oxygen to slow down fires.
Well, you can breathe it, although it will result in oxygen toxicity. This doesn't have anything to do with fires, and the gas doesn't have to be "more massive" than O2 to retard fires either.
Low pressure (100-200 mbar) pure oxygen behaves similarly to low partial pressure atmosphere in inert diluate (i.e. air). It's not perfect -- things still burn faster without the diluent -- but it's not as dangerous as pure O2 at sea level pressure, nor is it like the high-pressure pure O2 environment in the Apollo 1 test.
Also, N2 (and especially Ar) aren't consumed to an appreciable degree. They can be recycled in an artificial life support system (as they are, and have been, for decades).
Apollo used pure oxygen, and skylab was 3/4 oxygen, 1/4 nitrogen. For context, this was done to simplify systems, and lower the pressure in both the spacesuits and spacecraft; low-pressure in the spacesuit is important because it makes the suit more flexible.
Didn’t the full-oxygen Apollo 1 burn in a horrific accident while still on launchpad, and is the reason why doors can now open from the outside? One scratch and even iron burns in a 100% oxygen atmosphere. Honor to those 3 astronauts.
It would be a comic turn of fate if we succeeded to turn the Moon into an oxygen-rich atmosphere, only to discover that we can’t land on it because every single rocket we sent on it burns upon landing.
The problem was that it was full pressure, 1 atmosphere of pure oxygen. That was stupid and was only really done on that test, because it was a sea level mock-up. The actual spacecraft operated at just the normal oxygen partial pressure, but with no other trace gasses aside from exhaled CO2.
Apollo 1 was particularly bad because they were attempting to simulate relative space pressure on the ground. So they pushed the internal pressure up to 20 psi of pure O2 (sea level is ~15 psi).
That is something like ~7 the Oxygen density of normal air. Things burn hot and fast in that environment.
NASA page on In-Situ Resource Utilization: https://www.nasa.gov/isru
NASA Swamp Works: https://technology-ksc.ndc.nasa.gov/featurestory/swampworks
Dr. Phil Metzger, who worked for a long time at Swamp Works before taking a research position at a university. Still very much involved in processing regolith and moon bases. https://twitter.com/DrPhiltill
NASA also hosts an annual competition around regolith collection called the NASA Lunabotics Competition. The last 2 years have been a little rough, with a cancellation due to government furloughs, then a cancellation due to the pandemic. Swamp Works engineers, technicians, and machinists attend and are often judges. Where they might make 1 or 2 prototypes per year, they're able to see 30-50 different designs and see their performance. The rules are setup to penalize activity similar to the incentives NASA has. Low bandwidth usage, high material collection, and low vehicle weight are all rewarded. https://www.nasa.gov/offices/education/centers/kennedy/techn...
Alabama has had a very good run, accomplishing fully autonomous 10 minute competition runs, avoiding rocks, having a really great systems engineering approach.
There has also been a competition in Hawaii on Mauna Kea periodically. I was at Iowa State in 2014 when we attended. There's an area just west of the visitor center with an environment very similar to the moon. Teams tele-operated the robots from ~30 miles away in Hilo, introducing a time lag in communications. It was a really incredible experience, and a lot of logistical planning to ship a robot, spare parts, and tool to Hawaii. Dremels are never the right tool for the job...but a lot of jobs can be done with a Dremel. Here's a video from Alabama at the same site in 2012. https://www.youtube.com/watch?v=mqWpglIwOr4